SemiBase

Variety V[6543]

The variety generated by [6, 6543]: all semigroups that satisfy every identity of [6, 6543]. 2 semigroups of order six generate it, and 4,912 semigroups of order six lie in it.

Shortest known basis

4 identities irredundant

  1. x² ≈ x⁴
  2. xyx ≈ xyx³
  3. x³yz ≈ xyzx²
  4. xyxztz ≈ xyzxtz

Irredundant: none of these identities follows from the others; for each, a semigroup satisfies the others but not it. Obtained from a certified basis by removing identities that follow from the others (Vampire). Shortest known, not known to be minimal.

Certified bases

Among the 505 varieties

V[9937]V[6211]V[6536]V[6598]V[6543]
Directly above
Directly below

A variety lies above another when it contains it. An inclusion holds when the basis of the smaller variety derives that of the larger one, proved by Vampire; it fails when a semigroup of order six lies in the one and not in the other.

Explore V[6543] in the inclusion graph, with everything above and below it.

Generated by 2 semigroups of order six

Contains 4,912 semigroups of order six

The semigroups of order six that satisfy the basis.

Show all 4,912